Obviously, no the bayonet makers were not related to the rifle makers, nor was there any direct coordination between them and the contracts with the military. At least not during the wars, I think there were some cases where Mauser worked with other companies for contracts, Mauser and Simson (Simson worked for Mauser for elements of a military contract), the Suhl consortium obviously collaborated with one another and probably outsiders to fulfill military contracts, - and Mauser did own the company, or had significant interest, in the firm that actually made the Mauser marked Sg98/05's ("Unionwerk Mea" I believe). Jon Speed and his books may be the best information on the actual relationship between Mauser and Unionwerk Mea... Jon Speed did share some details with me on this relationship, but i would have to review them to speak knowledgeably on the subject. I think it is almost a certainty that Mauser did not deliver the bayonets with the rifles though...
All that said, it is common for collectors that have a Mauser Gewehr98 to mate it with a Mauser made (Unionwerke actually) bayonet, - I know I did when I owned both. But other than having a mild case of a obsessive-compulsive disorder the practice is not reflective of actual events (what occurred)
